Binder composition for electrode

Abstract

An object of the invention is to provide an electrode material slurry for preparation of lithium-ion secondary batteries favorable in properties and superior in storage stability and an aqueous binder composition for lithium-ion secondary batteries that can be used for production of lithium-ion secondary batteries superior in discharge rate characteristics and cycle characteristics. Provided is a binder composition for lithium-ion secondary battery electrode, comprising polymer particles containing (a) an ethylenic unsaturated carboxylic ester compound and (b) an ethylenic unsaturated sulfonic acid compound at a (a)/(b) mass ratio of (98 to 91)/(2 to 9) in a total (a) and (b) amount of 70 mass % or more, based on the monomeric raw materials.

The invention claimed is:  
     
       1. A binder composition for electrode, comprising polymer particles containing (a) an ethylenic unsaturated carboxylic ester compound and (b) an ethylenic unsaturated sulfonic acid compound at a (a)/(b) mass ratio of (98 to 91)/(2 to 9) in a total (a) and (b) amount of 70 mass % or more, based on the monomeric raw materials,
 wherein the ethylenic unsaturated carboxylic ester compound (a) contains an ethylenic unsaturated carboxylic ester compound having one or more hydroxyl groups in the alcohol region (a1) and the content of the compound (a1) is 1 to 9 mass % on the total amount of the raw monomers, and 
 wherein the ethylenic unsaturated carboxylic ester compound (a) contains an ethylenic unsaturated carboxylic ester compound having multiple (meth)acrylic groups and/or (meth)allylic groups (a2) and the content of the compound (a2) is 1 to 10 mass % based on the total amount of the raw monomers. 
 
     
     
       2. The binder composition for electrode according to  claim 1 , wherein the ethylenic unsaturated carboxylic ester compound (a) contains additionally an ethylenic unsaturated carboxylic ester compound having an alkyl group having a carbon number of 8 or more in the alcohol region (a3) and the content of the compound (a3) is 10 to 90 mass % based on the total amount of the raw monomers. 
     
     
       3. The binder composition for electrode according to  claim 2 , wherein the ethylenic unsaturated carboxylic ester compound (a) contains additionally (a4) an ethylenic unsaturated carboxylic ester compound having an alkyl group having 1 to 7 carbon atoms in the alcohol region and the content of the (a4) is 1 to 30 mass %. 
     
     
       4. The binder composition for electrode according to  claim 1 , further comprising (c) an ethylenic unsaturated carboxylic acid, wherein the content of the ethylenic unsaturated carboxylic acid is 0.1 to 1.0 mass %. 
     
     
       5. An electrode material slurry, comprising the binder composition for electrode according to  claim 1  and an active material. 
     
     
       6. An electrode produced by using the electrode material slurry according to  claim 5 . 
     
     
       7. A secondary battery produced by using the electrode according to  claim 6 . 
     
     
       8. An electric double-layer capacitor produced by using the electrode according to  claim 6 .